Post-Haste by Post Horse?

Access to news and reliable information has always been crucial to those who exercise political or economic power. In the past, communication by letter between a king and his officials, as well as with other rulers, was the cornerstone of effective authority and diplomacy, and contact by letter between merchants was the key to successful business and trade. But the process of exchanging correspondence in medieval Europe was often inordinately slow. The rate at which letters might be conveyed from sender to recipient depended upon the physical endurance of a rider and his horse, travelling as far as they could during daylight hours. A horse is capable of achieving remarkable speeds over relatively short distances, but on prolonged journeys it cannot match the stamina of a man. Delays incurred by the frequent need to rest a horse when undertaking a protracted errand therefore meant that even the royal couriers of medieval Europe undertook many of their official journeys on foot.